#373F5F
Closest named color: Dark Grey Blue (#29465B). oklch(37.5% 0.056 272.7), rgb(55, 63, 95).
Aa
White text reads best on this color (10.30:1).
About this color
#373F5F is a dark, muted blue. In OKLCH its lightness is 38%, its chroma 0.056 and its hue 273°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Grey Blue (#29465B), ΔE 0.030 away. White text reads best on it, at 10.30:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | muted (0.056) |
| Temperature | cool |
| Nearest name | Dark Grey Blue (#29465B) |
| Black text | 2.03:1 |
| White text | 10.30:1 |
Values
| HEX | #373F5F |
| RGB | rgb(55, 63, 95) |
| HSL | hsl(228, 27%, 29%) |
| OKLCH | oklch(37.5% 0.056 272.7) |
Contrast
WCAG 2 contrast ratios are the conformance target: AA needs 4.5:1 for body text and 3:1 for large text, AAA needs 7:1. APCA Lc values are supplementary guidance from the WCAG 3 drafts.
| Pair | WCAG 2 | Result | APCA | APCA guidance |
|---|---|---|---|---|
| White text on #373F5F | 10.30:1 | AAA | Lc -97.9 | Preferred for body text |
| Black text on #373F5F | 2.03:1 | Fails | Lc 10.0 | Not readable |
| #373F5F text on white | 10.30:1 | AAA | Lc 93.9 | Preferred for body text |
| #373F5F text on black | 2.03:1 | Fails | Lc -8.7 | Not readable |
Tints and shades
A 50–950 scale built in OKLCH: the hue is held, lightness follows a Tailwind v4-like curve, and every step is kept inside the sRGB gamut. This color sits at step 900.
-
Step 50
50
#F4F5F9
oklch(97.1% 0.005 275)
-
Step 100
100
#E7E9F2
oklch(93.5% 0.012 276.1)
-
Step 200
200
#D4D9E9
oklch(88.6% 0.023 272)
-
Step 300
300
#B7BFDD
oklch(80.8% 0.043 273.6)
-
Step 400
400
#929ECB
oklch(70.6% 0.067 273)
-
Step 500
500
#7886BE
oklch(63.1% 0.086 272.9)
-
Step 600
600
#616FAA
oklch(55.6% 0.093 272.9)
-
Step 700
700
#505D92
oklch(49.1% 0.087 272.4)
-
Step 800
800
#424C76
oklch(42.7% 0.071 272.9)
-
Step 900
900 (this color)
#373F5F
oklch(37.5% 0.056 272.7)
-
Step 950
950
#202538
oklch(26.9% 0.036 272.4)
#373F5F with color blindness
Simulated with the Machado et al. (2009) model. ΔE is how far the color moves: below about 0.02 you would not notice a change.
| Vision | Seen as | Shift (ΔE) |
|---|---|---|
| Protanopia (no red cones) | #344260 | 0.010 |
| Deuteranopia (no green cones) | #313F5E | 0.009 |
| Tritanopia (no blue cones) | #2B454A | 0.050 |
| Achromatopsia (no color) | #404040 | 0.056 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373F5F
#373F5F
oklch(37.5% 0.056 272.7)
- #4B401B
#4B401B
oklch(37.4% 0.056 93)
Analogous
Neighbouring hues, 30° either side.
Split complementary
The two hues beside the complement (150° and 210°).
Triadic
Three hues spaced 120° apart.
Palettes with this color
Curated palettes that contain a color within ΔE 0.04 (OKLab) of #373F5F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Grey Blue #29465B ΔE 0.030
- Charcoal #264653 ΔE 0.041
- Dark Blue Grey #1F3B4D ΔE 0.048
- Prussian Blue #1D3557 ΔE 0.052
- Charcoal Grey #3C4142 ΔE 0.053
- Onyx #343A40 ΔE 0.054
- Twilight Blue #0A437A ΔE 0.059
- Marine Blue #01386A ΔE 0.064
Use #373F5F in your product
Turn it into light and dark UI roles checked for contrast, then export to Tailwind v4, shadcn/ui, CSS or design tokens.